I’ve built a simple signal processing pipeline, and I feed it signals from the EPOC’s neurodata stream. Once the brainwaves are transformed into frequency space, I do some filtering and then emit an audio signal that’s synthesized by using an inverse FFT. The raw sine waves are a bit brutal on the ears, so I also drive the MIDI device with pitches that corresponding to various brainwave frequencies. This produces some interesting sci-fi sound effects that resemble the score to the last act of 2001: A Space Odyssey.